1. Field of the Invention
The present invention relates to a battery check device for performing a check of the voltage of a battery power source supplying power to a device, such as a camera or other device using a battery power source, at the time of use of the device.
2. Description of the Related Art
Battery check circuits for cameras are known which perform a voltage check of a built-in battery power source at the time of camera use. The battery check is performed, for example, by a main switch of the camera or other switch which is set ON when a camera release button is depressed. If the voltage of the battery power source is determined to be above a battery check voltage, the operation of the camera proceeds to the next sequence of camera actions. However, if the voltage of the battery power source is determined to be below the battery check voltage, the camera is set to an inactive state.
When the known battery check circuits read the battery voltage at a battery check time, a load placed on the battery causes the battery voltage to decrease. If the battery voltage read at the battery check time is above some constant value of voltage (i.e., above the battery check voltage) a satisfactory battery check indication is given. The battery power source for the camera has the characteristic that the battery voltage recovers after a period of time. When the battery has not been used for a long period and a normal battery check is performed, the battery voltage is above the battery check voltage; however, when performing photography plural times using the battery, a problem arises in that the battery voltage ends up below the battery check voltage causing an unsatisfactory battery check indication. In particular, when performing strobe photography, because the consumption of battery current is very large, the above-described phenomenon occurs.